WO2000011595A1

WO2000011595A1 - Apparatus and method for marking elongated articles

Info

Publication number: WO2000011595A1
Application number: PCT/CA1999/000769
Authority: WO
Inventors: Jacques Labbe; Sylvain Bilodeau
Original assignee: Centre De Recherche Industrielle Du Quebec
Priority date: 1998-08-20
Filing date: 1999-08-19
Publication date: 2000-03-02
Also published as: NO20010867D0; AU5366399A; BR9913056A; NO20010867L; CA2245412C; NZ510537A; EP1105830A1; CA2245412A1

Abstract

An apparatus for marking elongated articles such as lumbers (11) while being longitudinally conveyed, and for providing a reliable reading of the applied marks (41, 43, 45, 47) to obtain associated coded information related to the article. The apparatus comprises a marking station (10) followed by a remote reading station (48). The elongated article is transported on a longitudinal conveyor through the marking station (10) which receives coded information related to the article to be marked, such as identification and/or grade/dimension data. The reading station (48) comprises upper and lower pairs of luminescent ink-jet devices (30) for applying a corresponding information mark pattern (41, 43, 45, 47) on either or both top and under surfaces of the elongated article, which information mark pattern longitudinally extends on each of the marked surfaces. After being handled, the marked article is transferred to a transversely moving conveyor (49), which transports the marked article through the reading station which is provided with a plurality of optical sensing devices (61, 62, 63, 64) each having luminescence inducing light source, to produce an output signal corresponding to the coded information. A method for marking and reading coded information onto an elongated article ensures reliable article identification whenever the article was turned upside-down while being handled between marking and reading steps.

Description

APPARATUS AND METHOD FOR MARKING ELONGATED ARTICLES Field of the invention

The present invention relates to the field of automated handling of articles, and particularly to automated article marking apparatus and methods for providing information about articles being handled. Background of the invention

During the past years, computer-based technology has been increasingly applied to the handling of articles during the manufacturing or processing stages, to improve productivity. Typically, in an automated production or processing line, the data related to articles or components thereof are recorded in sequence prior or during their handling in computer memories provided on programmable computers or controllers which are programmed to command specific operations to carry out for each article or component, such as sorting, storing, etc. In cases where the initial sequence of articles under handling can be strictly maintained throughout the process, the integrity between recorded data and related articles is ensured. Otherwise, some means should be provided to make sure that each article is always associated with the corresponding recorded data, irrespective of any change in sequence that may have occurred during the process.

A well known approach of control data integrity consists in physically applying an information code onto the article, either manually or through automated means, to allow data entry downstream of the process, either through an operator interface or through an automated data input device. The information code associated with each article can be either a unique identification code for that particular article which allows the retrieval of the article-related data as previously recorded, or a code directly representing the data corresponding to that particular article. Such a known approach is applied by the marking apparatus disclosed in US Patent No. 4,172,417 issued on Oct. 30, 1979 to Fardeau et al., which apparatus applies marks of a bar-code type by spraying fluorescent ink onto each article moving rapidly, the position of marks with respect to a reference point being set according to a coding language. The applied bar-code can then be read through scanning by a known optical code reader, and then be converted into identification or any other article-related data.

Many marking methods have been developed for use in the lumber processing industry for which the integrity of handling information is essential in many cases. In US Patent No. 4,638,440 issued on Jan. 20, 1987 to Brough et al., there is disclosed a data entry and feeding system for a lumber trimmer receiving lumbers on top of which trim and grade marks were previously applied by operators at a grading station, in a non computer-readable format. Upstream of a transversal lug loader is a data entry zone where each lumber is temporarily brought at rest on a smooth chain conveyer, enabling an operator to examine the lumber and to enter trimming and grading information through an operator panel. A programmable logic controller provided with a shift register commands feeding of the lumber to the lug loader according to a first-in, first-out sequence, thereby causing one or more selected trimming saws to make the proper cuts. Although such prior art system provides automated trimming and sorting of lumbers, marking and data entering operations still require intensive operator attendance, limiting accordingly processing rate and production.

In US Patent No. 4,924,088 issued on May 8, 1990 to Carman et al., there is disclosed an automated apparatus for reading information marks manually applied by graders to wood products such as lumbers, which apparatus is used as part of a trimming and/or sorting process. The apparatus comprises an information reading device using a camera for transferring video images to an image processor identifying the coded information, Individual graders use different color fluorescent markers, in a such manner that the grader identification can be obtained through the use of either a pair of cameras with appropriate color filters or a single RGB camera. As for many other prior marking systems, the apparatus of Carman et al. still involves manual marking, thus limiting the productivity accordingly.

In US Patent No. 4,392,204 issued on Jul. 5, 1983 to Prim, there is disclosed a lumber marking system for applying a numerical code onto the end of each lumber through an embossing mechanism, after the lumber was moved past a visual inspection station where a viewing operator entered grade data into a controller via a console, and moved past length/width optical measuring stations. The resulting grade, length and width data are used by the controller to cause the embossing mechanism to apply the numerical code, each digit of which corresponds to a value of a lumber parameter, i.e. grade, length or width. Although that marking system does not require the operator to manually apply information mark onto each lumber, processing rate is still dependent on the operator capacity of manually entering the grading data into the controller through the operator console, which limits the marking rate.

Therefore, there is still a need for an apparatus and method for marking articles which obviate the foregoing limitations of the prior art. Summary of invention

It is therefore an object of the present invention to provide an apparatus and method for marking elongated articles while being longitudinally conveyed, and for providing reliable reading of the applied marks to obtain the associated coded information.

According to the above object, from a broad aspect of the present invention, there is provided an apparatus for applying and reading an information mark pattern onto an elongated article to be transferred from longitudinally moving transport means to transversely moving transport means. The apparatus comprises a marking station adapted to receive coded information related to the article and comprising marking means for applying corresponding said information mark pattern onto the article while being carried by the longitudinal transport means, said information mark pattern longitudinally extending onto the article. The apparatus further comprises a station for reading the information mark pattern applied on the article after transfer thereof to the transverse moving transport means, to produce an output signal corresponding to the coded information.

According to a further broad aspect of the present invention, there is provided a method for applying and reading information marks onto an elongated article to be transferred from longitudinally moving transport means to transverse moving transport means, said method comprising the steps of a) receiving coded information related to the article; b) applying corresponding said information mark pattern onto the article while being carried by the longitudinally moving transport means, said information mark pattern longitudinally extending onto the article; and c) reading the information mark pattern applied on the article after transfer thereof to the transverse moving transport means, to produce an output signal corresponding to said coded information.

Brief description of drawings

A preferred embodiment of an apparatus and method according to the present invention will now be described with reference to the accompanying drawings in which: Fig. 1 is a side elevation view of a marking station as part of a marking apparatus according to a preferred embodiment of the present invention;

Fig. 2 is a partial end view of the marking station of Fig. 1, showing the ink- jet device used to apply information marks on a lumber passing throughout the marking station; Fig. 3 is a side elevation view of a reading station as part of a marking apparatus according to the preferred embodiment of the present invention;

Fig. 4 is a cross-sectional top view according to line 4-4 of the reading station of Fig. 3;

Fig. 5 is a cross-sectional end view according to line 5-5 of the reading station of Fig.3;

Fig. 6 is a partial side elevation view of the reading station of Fig. 3, showing the optical sensing devices disposed under the lumber conveying plane;

Fig. 7 is a top view of the optical sensing devices of Fig. 6;

Fig. 8 is a partial side elevation view of reading station of Fig. 3, showing the optical sensing devices supported over the lumber conveying plane ;

Fig. 9 is a partial end view of the pivoting holder for the optical sensing devices of Fig. 8, which is shown in a lowermost reading position;

Fig. 10 is a cross-sectional view according to line 10-10 of Fig. 8, showing working and storage positions for the optical sensing devices; Fig. 11a is an example of a lumber as marked using the apparatus and method according to the present invention, showing a mark pattern corresponding to one of a sequence of information codes;

Fig. 1 lb is another example of a marked lumber, showing a mark pattern corresponding to another one of the information codes sequence;

Figs. 12a to 12d illustrate a selected sequence of article identification codes that could be used according to the preferred embodiment of the present invention. Detailed description of the preferred embodiment Referring now to Fig. 1, there is depicted a marking station generally designated at 10 as part of an apparatus in accordance with the present invention. Although the example shown relates to lumber marking, it should be understood that the present invention may be advantageously used in any application where elongated articles has to be marked to ensure the integrity of the information required for further processing. Marking station 10 has a frame 12 provided with access cover 12', and standing on front and rear pairs of legs 13, on which frame 12 is mounted a belt conveyor 14 having an adjustable driven roll 15 provided with an adjustment mechanism 16 and extending from a rear portion of station 10 to a front portion thereof where a driving roll 17 coupled to a driving motor (not shown) is mounted. Typically, conveyor 14 can be used as the output conveyor of an adjacent upstream grading/measuring station (not shown), where a lumber 11 was inspected for detecting surface defects such as holes, wane or knots, and was physically measured to obtain its dimensions, to provide information required for later grading and/or sorting. As known in the art, the inspection step may be carried out at a viewing station where lumbers travel in sequence past one or more operators who assign to each lumber a grade based on the assessment of the appearing lumber quality. Alternatively, the inspection can be performed using an automated grading station such as that disclosed in PCT published application No. WO 98/7023 dated Feb. 19, 1998 and naming the present assignee, or using any other of the inspection devices of the prior art such as those disclosed in Patent documents US 4,827,142, WO 95/24636 or EP 692714. Although the lumber measurement may be carried out manually, a known automated measuring equipment is preferably used. Measurement and grading functions may also be integrated in a single equipment such as the station disclosed in WO 98/7023. When an operator viewing station is used, it must be provided with some data entry means such as a keypad, to generate a computer readable data input signal representing the information as entered, and in cases where an automated grading/measuring equipment is employed, a proper interface must be used to generate such an input signal. The input data is fed to a data converter 19 which generates the article identification and/or grade/dimension code data, which is in turn fed through a line 18 to a marking controller 21. Where only article identification data is generated, the same input data is also transmitted through a line 20 to a remote processor 86 as shown in Fig. 3, where it is stored in memory, as will be later explained in more detail.

As shown in Fig. 1, the marking controller 21 has an output line 22 being connected to a controlled input of a fluid pump 24 as part of an ink supply unit 26 further having an ink storage tank 28 in fluid communication with pump 24. Through an input line 25, marking controller 21 receives a triggering signal from an optical presence detector 27 of a known construction, and through an input line 23. Controller 21 also receives a conveyer belt position signal from a conventional position sensor 29 installed on the conveyer 14, to generate a control marking signal through line 22, as will be later explained in more detail. Ink under pressure is supplied to an ink-jet device generally designated at 30, comprising upper and lower pairs of ink-jet nozzles 32, 32' and 34, 34' as better shown in Fig. 2. It can be seen that in operation, only single ink-jet nozzles 32 in the upper pair and nozzle 34 in the lower pair are actually needed, which are directed to form transverse ink-jets shown at numerals 36 and 36' respectively, for applying ink mark onto the lumber opposed surfaces. Nozzles 32' and 34' are auxiliary nozzles provided in case of failure of main nozzles 32 and 34, to avoid maintenance interruption. Although a single pair of upper or lower nozzles may be used in case where a single surface of the lumber has to be marked, it has been found advantageous to provide two pairs of nozzles to allow marking on two corresponding series of marking areas associated with top and under surfaces 31, 31 ' of lumber 11, as will be later explained in more detail. Marking ink used preferably exhibits fluorescent characteristics to be clearly detectable under suitable short wavelength illumination (ultraviolet), while being substantially invisible under ambient light, as being explained later in more detail. A fast drying, isopropylic alcohol-based solution containing fluorescent agent is preferably used. Pairs of ink-jet nozzles 32, 32' and 34, 34' are mounted on adjustable holders 38 and 40 providing adjustment of both the angular orientation of nozzles and spacing thereof from the lumber conveying plane 42, to obtain the desired marks having sufficient width to allow a reliable reading. Ink-jet device 30 is preferably covered by an exhaust hood 44, which are illustrated in dotted line in Figs. 1 and 2, to collect secondary ink mist produced by nozzles 32, 34 during marking.

A reading station according to the preferred embodiment of the present invention will be now described with reference to Figs. 3 to 10. Referring to Figs. 3 to 5, the reading station generally designated at 48 is installed on a conventional transverse conveyor 49 having a guide plate 52 and provided with a series of belt driven rolls 53 mounted for rotation on lower beam 57 to urge the fed lumbers against the guide plate 52 as indicated by arrow 55. Transverse conveyer 49 has narrow chains 56 mounted on driving axle 59 coupled to a motor (not shown) and arranged in a parallel spaced relationship. Chains 56 are provided with mutually aligned series of lugs 54 adapted to engage trailing edge of lumber 11 for moving thereof in a transverse direction as indicated by arrow 58 toward a downstream processing station (not shown), such as a sorting or trimming station. As better shown in Fig. 8, the reading station comprises a holder 51 for maintaining a series of optical sensing devices 61, 62, 63, 64 in a transverse spaced relationship facing corresponding top marking areas 41, 43, 45, 47 on lumber 11 in a reading position as shown in Fig 8, to scan an information mark pattern applied on a top surface 31 of lumber 11 transported through a conveying plane 60. It can be seen that the first marking area 41 is located near the first or proximal end 33 of lumber 11, which has also a distal end 35. Other marking areas 43, 45, and 47 form a distinct group which is spaced from the marking area 41. The purpose of such arrangement of marking areas is to allow an optinal manual marking of any out-of-sequence lumber, as will be described later in more detail. The holder 51 comprises a transverse shaft 66 extending under an operator access platform 76 as shown in Fig. 3, and being mounted for rotation at opposed ends thereof on vertically extending side posts 68, 70 forming a frame rigidly secured to floor by attachments 50, 50', as better shown in Fig. 8. Adjustably secured along transverse shaft 66 are a plurality of support assemblies 71, 72, 73, 74 for respectively supporting sensing devices 61, 62, 63, 64, as will be later explained in more detail with reference to Figs. 8-10. Adjustably secured to the beam 57 are support assemblies 81 and 82, for respectively supporting sensing devices 61' and 62', 63', 64' which are arranged in a transverse spaced relationship facing the corresponding under marking areas 41 ', 43', 45', 47' in a reading position as shown in Fig 6, to scan the information mark pattern applied on under surface 31' of lumber 11. The reading station 48 further comprises data processor 86 provided with data buffer receiving through bundles of lines 88, 90 passing within transverse shaft 66 and transverse beam 57 respectively, the detected signals from upper and lower optical sensing devices 61, 62, 63, 64 and 61 ', 62', 63', 64' respectively. Where article identification code only is printed onto the lumber, the data processor 86 receives through line 20 for storing in a memory the same input data that was previously fed to data converter 19 as shown in Fig. 1, to allow correspondence between the input identification data and the grade/dimension data as required for further lumber processing. Referring to Figs. 6 and 7, lower optical sensing devices 61', 62', 63', 64' being identical, only sensing device 61 ' will be described in detail. Sensing device 61 ' is mounted within the enclosure 85 of an arm 83 at upper end thereof. Sensing device 61 ', which is of a known construction, comprises an ultraviolet light emitter 92 for producing ultraviolet radiation with a wavelength of approximately 365 nm to activate a fluorescent agent contained in the ink used to print marks onto the lumber surface, which in turn generates luminescent radiation in a visually detectable range typically between about 450 nm and 780 nm. A scanning receiver 94 is mounted at a position near light emitter 92 for sensing the luminescent radiation, to produce the detected signal either at switching or analog outputs provided on scanning receiver 94, which signal is transmitted toward data processor 86 through respective line 90 extending through lower beam 57, as better shown in Fig. 3. A dust removing device 95 adapted to be connected at an outlet 96 to a blower (not shown) is provided, which has an outlet nozzle 97 located adjacent a transparent protecting plate 98 disposed over light emitter 92 and scanning receiver 94. First optical sensing device 61' is preferably mounted on its own support 93 which is adjustably secured under lower beam 57, to allow independent transverse position adjustment of optical sensing device 61' over the end portion of the lumber, as will be later explained in more detail. Support assembly 81 comprises an holding member 100 to which is secured sensing device 61 ' with bolts 101 passing through mounting plate 99 and elongated slots 103 provided on holding member 100, and an adjustable mounting base 102 having a lateral wall 111 being rigidly connected with bolts 104 passing through elongated slots 107 provided on the lateral wall 111 to a plate 106 retaining proximal ends of short beams 105 having distal ends being secured to holding member 100. Adjustable mounting base 102 has a top wall 110 which can be attached to a bottom wall of beam 57 at a desired reading position with bolts 108 passing through elongated slots 109 provided on top wall 110. Lateral wall 111 and top wall 110 are rigidly maintained in their relative position with a pair of triangular bracing plates 112, as better shown in Fig. 5. Optical sensing devices 62', 63', 64' are mounted on the lower beam 57 in a similar way as for sensing device 61 ', with a support assembly 82 comprising a common holding member 100' and respective mounting plates 99, which provide proper relative spacing between optical sensing devices 62', 63' and 64'. A pair of short beams 105' are used to connect opposed ends of the holding member 100' to a pair of mounting bases 102' and 102" which are secured under transverse beam 57 in a similar manner as for mounting base 102 at a position providing alignment of the optical sensing devices 62', 63', 64' with the lower series of marking areas associated with the lower surface of lumber 11.

Referring now to Fig. 8, support assemblies 71, 72, 73, 74 being identical, only support assembly 71 will be described in detail. Support assembly 71 comprises an articulated support arm 113 having a first end being adjustably secured along shaft 66 through a base member 115 and a second end receiving optical sensing device 61. The base member 115 comprises a lower flanged plate 117 to which the arm first end is rigidly secured and an upper flanged plate 119, which plates 117 and 119 are clamped onto shaft 66 through two pairs of bolts assemblies 121. Support arm 113 comprises first and second portions 123, 125 which are pivotally connected at their respective ends 122, 124 as shown in Fig. 10, by an articulation 127 comprising a hinge pin 129 and a U-section covering member 131 being secured to first portion 123 and traversed by pin 129. Respective surfaces of ends 122 and 124 show opposed beveled edges 133 and 135 provided with abutments 130 and 130', which edges 133, 135 form a right angle at the location of the pin 129, arm 113 being in a full extended reading position as illustrated in solid lines in Fig. 10. In a storage position as shown in truncated lines, abutments 130, 130' are caused to mate, allowing edges 133 and 135 to be maintained in a stable parallel relationship. It is pointed out that the second portion 123 of arm 113 is maintained in a normal orientation with respect to top surface 31 of lumber 11 while being displaced between full extended reading and storage positions, thereby height adjustment of the sensing unit 61 with reference to lumber top surface 31 in a reading position can be provided. Optical sensing device 61, which is of a same construction as for sensing device 61' which is described before with reference to Fig. 6, is mounted within enclosure 112 of support arm 71 at a lower end thereof. It is pointed out that as opposed to lower sensing device 61 ', a dust removing device is normally not required to ensure proper operation of sensing device 61. Secured on posts 68 and 70 through bolts 138, 140 are rotary bearing units 137, 139 through which shaft ends 141, 143 respectively extends. Shaft end 143 is rigidly secured to a sleeved head 144 of a connecting rod 145 through a set screw 147, as better shown in Fig. 9, which rod 145 has a levering member 149 on which is pivotally mounted a driving rod 151 as part of a pneumatic cylinder 153 having a base member 157 being pivotally secured to post 70 through a bracket 157. Levering member 149 is maintained in a lower position through an adjustable abutment 155 secured to post 70 through an attachment 160 shown in Fig. 8.

Method of operation of the preferred embodiment of the present invention will now be explained. Referring to Figs. 12a to 12d, there is schematically illustrated a full sequence of 256 (, wherein number of digits =8) different codes 161 that can be formed with 8 digits that are given binary values (black:! ,white:0), which codes are numbered from «00» to «FF» in the hexadecimal notation appearing above each of the illustrated codes 161. It can be seen that to each code 161 corresponds an under numeral associated with a selected identification sequence of codes, as will be explained later in more detail. It can be seen from Figs. 12a to 12d that each identification code 161 is structured into two sets of complementary code data represented by right and left adjacent columns of digits 163, 163' respectively corresponding to two complementary portions of a mark pattern, with uppermost digits relating to the proximal or first end 33 of lumber 11, which mark pattern portions are respectively applied onto top and under surfaces 31, 31' of the lumber. For example, Fig. 11a illustrates a lumber 11 ' onto which an information mark pattern corresponding to code «FF» has been applied, while Fig. 1 lb illustrates a lumber 11 " onto which an information mark pattern corresponding to code «29» has been applied, at marking areas 41, 43, 45, 47 and 41', 43', 45', 47' for both lumbers 11 ' and 11 ". With such a double surface marking, the maximum number of available identification mark patterns is significantly increased compared with a single surface marking method using a same number of marking areas per lumber surface.

However, to obtain reliable double surface marking using all codes of a sequence, one must ensure that the inspected lumber presents a same surface orientation at the reading station as its surface orientation at the marking station. Whenever a lumber was turned upside-down after leaving the marking station and before reaching the reading station, such as during quality control handling, that lumber should ideally be replaced in its original orientation before being transferred to the reading station. However, such a manual turning cannot be practically done by an operator, who cannot detect such wrong lumber position. According to the preferred method of identification coding of the present invention, any manual turning is obviated by associating pairs of identification codes which are considered as equivalent whenever lumber surfaces have been inverted. It can be seen from Figs. 11a to l id that 16, i.e. (), article identification codes have symmetrical complementary code data, which corresponds to the codes « 00, 11, 22, 33,..., 99, AA, BB, CC,..., FF ». Data columns 163, 163' for these codes being symmetrical, these particular codes are not permutable and thus cannot be associated with any other equivalent codes. For a sequence of different codes, there are such symmetrical codes. The remaining identification codes form pairs of equivalent codes, e.g. 120 pairs of such equivalents codes for =8. The complementary data of a selected one of equivalent codes form the other one of the equivalent identification codes when being permuted one another, thereby ensuring article identification whenever the article surfaces have been inverted between the marking and reading stations. Thus, according to that method, the maximum number of available identification mark patterns is given by , e.g. 136 pairs of available identification mark patterns for =8, which correspond to decimal numbering appearing under each illustrated code. In Fig. 12a to 12d, each identification code associated with a selected identification code is crossed out to indicate that any of them can be used for marking. It can be seen in Fig. 12a that code «00», also identified at under numeral «-101» indicating a first exclusion from the selected identification sequence, is also crossed out as being unusable, to prevent generation of an identification signal whenever a lumber is missing at a given location on the transversal conveyor.

Alternatively, when a high maximum number of available identification mark patterns is not required, a same marking pattern can be applied to both surfaces of the lumber to provide positive identification irrespective of the lumber orientation.

Furthermore, to avoid associating an out-of-sequence lumber that was manually fed to the transversal conveyor by an operator, all codes showing a «0» digit at the two uppermost marking areas, such as codes «04», «08» and «0C» identified by a second exclusion under numeral «-102 » in Figs. 12a to 12d, are also crossed out to yield a selected sequence of 126 codes, in a such manner that any out- of-current sequence lumber which was intentionally fed with distal end 35 next to the guiding plate rather than next to proximal end 33 as shown in Figs. 1 la and 12a, cannot be associated with any code of the current sequence, by preventing scanning of marking areas 41, 43 and 41', 43' respectively. Hence, any previously used code of a distinct sequence associated with a prior series of processed lumbers cannot be related to a lumber of a currently processed series of lumbers associated with the current sequence. Alternatively, as better shown in Fig. 8, first marking areas 41 and 41 ' can be reserved for use by the operator to manually apply a mark on any out-of- current lumber with a luminescent hand-held marker before passing through the reading station, which produces a signal indicative of an out-of-current sequence lumber whenever an applied manual mark is detected. In such case, an additional upper optical sensing unit can be inserted between sensing unit 61 and 62, with an additional support arm 113.

In operation, referring to Fig. 1, lumber 11 to be marked coming from a manual or automated grading/measuring station is longitudinally fed to the input end of conveyor 14 as indicated by arrow 165. According to a first mode of operation, input signal corresponding to fed lumber 11 as generated at the grading/measuring station is fed to data converter 19 which generates identification coded data, which is in turn fed through line 18 to marking controller 21. Same input data is also transmitted through line 20 to remote processor 86, as shown in Fig. 3, where it is stored to allow data correspondence upon information mark pattern reading.

According to a second mode of operation, the data input signal is converted to a data code representing lumber grade/dimension information, which is associated with a corresponding information mark pattern to be applied to one or more surfaces of the lumber 11. In that case, data converter 19 is used to provide proper format for the coded data to be fed to marking controller 21. According to a third mode of operation, both identification data and grade/dimension data are generated in a proper coded format by converter 19 and are then fed to marking controller 21. It is pointed out that for the second and third operation modes, output line 20 is not required to provide data correspondence at the reading stage. According to the received triggering signal and conveyer belt position signal from lines 25 and 23 respectively, coded data is processed by marking controller 21 to produce the marking control signal which is sent to ink supply unit 26 through line 22, which control signal shows a proper timing sequence to operate ink-jet device 30 according to the arrangement of longitudinally spaced marking areas on moving lumber 11, in a such manner that the so applied marks longitudinally extend onto article 11 at a predetermined mark length. Marked lumber 11 may then be transferred to a further conveyor for handling purpose, before being transferred to transversal conveyor 49 as shown in Figs. 3 and 4, trough the input longitudinal conveyor formed by idle rolls 53. While proximal end 33 of the lumber is maintained in abutment with guide plate 52, a next one of the aligned series of lugs engages with the trailing edge of the lumber as chains 56 transversal conveyor 49 are being indexed in the direction of arrow 58 as shown in Fig. 4 past reading station 48, in a such manner that all marking areas 41, 43, 45, and 47 and/or 41 ', 43', 43' and 45' are scanned by sensing devices 61, 62, 63, 64 and/or 41, 43, 45 respectively, before leaving apparatus 10, for further processing purpose. It is within the ambit of the present invention to cover any obvious modification of the described embodiment of the apparatus and method according to the present invention, provided it falls within the scope of the appended claims.

Claims

1. An apparatus for applying and reading an information mark pattern onto an elongated article to be transferred from longitudinally moving transport means to transversely moving transport means, said apparatus comprising; a marking station adapted to receive coded information related to said article and comprising marking means for applying corresponding said information mark pattern onto the article while being carried by the longitudinal transport means, said information mark pattern longitudinally extending onto the article; a station for reading said information mark pattern applied on the article after transfer thereof to the transverse moving transport means, to produce an output signal corresponding to said coded information.

2. An apparatus according to claim 1, wherein said article is a lumber.

3. An apparatus according to claim 1, wherein said reading station comprises optical sensing means for scanning said information mark pattern and having an output being coupled to data processor means to produce said output signal.

4. An apparatus according to claim 3, wherein said information mark pattern is formed by at least one mark applied on a selected marking area of at least one series of marking areas arranged on the article in a predetermined longitudinally spaced relationship, said mark representing one of binary values forming said coded information.

5. An apparatus according to claim 4, wherein said optical sensing means comprise a plurality of optical sensing devices disposed in a transverse spaced relationship facing corresponding said marking areas in a reading position to scan said information mark pattern, for producing at said output a plurality of signals corresponding to said coded information.

6. An apparatus according to claim 5, wherein said article has an under surface laying on said longitudinal transport means and a top surface, said top surface having one of said at least one series of marking areas, said plurality of optical sensing devices comprising an upper series of optical sensing devices disposed in a transverse spaced relationship facing corresponding said marking areas of said top surface in said reading position to scan at least a first portion of said information mark pattern.

7. An apparatus according to claim 6, said under surface having another one of said at least one series of marking areas, said plurality of optical sensing devices comprising an lower series of optical sensing devices disposed in a transverse spaced relationship facing corresponding said marking areas of said under surface in said reading position to scan at least a second portion of said information mark pattern.

8. An apparatus according to claim 6, further comprising means for adjustably holding said upper series of optical sensing devices between said reading position and a storage position remote from said top surface.

9. An apparatus according to claim 8, wherein said adjustable holding means comprise a frame to which are pivotally mounted opposed ends of a shaft transversely extending over said transversal transport means, means for rotating said shaft about its longitudinal axis, a plurality of support arms each having a first end being adjustably secured along said shaft and a second end for holding a respective one of said optical sensing devices, said second end being displaceable between said reading position and said storage position upon rotation of said shaft.

10. An apparatus according to claim 9, wherein each said support arm comprises first and second portions respectively including said first and second ends and being pivotally connected by an articulation, said second portion being substantially maintained in a normal orientation with respect to said top surface while being displaced between said reading and storage positions.

11. An apparatus according to claim 1, wherein said marking means comprise an ink-jet device facing said article and provided with valve means in fluid communication with ink storage means and controlling means adapted to receive said coded information to command activation of said valve means accordingly.

12. An apparatus according to claim 11, further comprising means for adjustably holding said ink-jet device in a marking position.

13. An apparatus according to claim 11, wherein said ink is fluorescent ink, said reading station comprising optical sensing means for scanning said information mark pattern and having an output being coupled to data processor means to produce said output signal, said apparatus further comprising illumination means for directing a beam of light onto the information marks while being scanned, said light being characterized by a spectrum containing an activating wavelength range for said fluorescent ink.

14. An apparatus according to claim 11, wherein said controlling means is adapted to command activation of said valve means according to a timing sequence causing each said mark to longitudinally extend onto the article at a predetermined mark length, said ink-jet device having nozzle means adapted to transversely distribute the ink onto the article at a predetermined mark width.

15. An apparatus according to claim 1, wherein said article has at least two surfaces, said marking station being adapted to receive said coded information for applying at least two complementary portions of said information mark pattern onto respective said surfaces.

16. A method for applying and reading information marks onto an elongated article to be transferred from longitudinally moving transport means to transverse moving transport means, said method comprising the steps of: a) receiving coded information related to said article; b) applying corresponding said information mark pattern onto the article while being carried by the longitudinally moving transport means, said information mark pattern longitudinally extending onto the article; c) reading said information mark pattern applied on the article after transfer thereof to the transverse moving transport means, to produce an output signal corresponding to said coded information.

17. A method according to claim 16, wherein said article is a lumber.

18. A method according to claim 16, wherein said marks are fluorescent marks, said method further comprising the step of directing a beam of light onto the information marks while performing reading step c), said light being characterized by a spectrum containing an activating wavelength range for said fluorescent marks.

19. A method according to claim 16, wherein said coded information comprises an article identification code.

20. A method according to claim 16, wherein said information mark pattern is formed by at least one mark applied on a selected marking area of one or more series of marking areas arranged on the article in a predetermined longitudinally spaced relationship, said mark representing one of binary values to form said coded information.

21. A method according to claim 20, wherein said article has at least two surfaces where at least two of said series of marking areas are respectively arranged, said step b) consisting of applying at least two complementary portions of said information mark pattern respectively onto said at least two series of marking areas.

22. A method according to claim 20, wherein said article has two surfaces where at least two of said series of marking areas are respectively arranged, said step b) consisting of applying two complementary portions of said information mark pattern respectively onto said two series of marking areas, said coded information comprising one of : i)an article identification code having symmetrical complementary binary code data corresponding to said complementary portions and being comprised within a code sequence; and ii) a selected one of a pair of equivalent identification codes having permutable complementary binary code data corresponding to said complementary portions and being comprised within the code sequence, the complementary code data of the selected one of said equivalent codes forming the other one said equivalent identification codes when being permuted one another, thereby ensuring said article identification whenever said surfaces have been inverted between said steps b) and c).